Ph. Svensson et L. Kloo, Metal iodides in polyiodide networks: Synthesis and structure of binary metal iodide-iodine compounds stable under ambient conditions, INORG CHEM, 38(14), 1999, pp. 3390-3393
The reaction between HgI2(C6N4H12) and HI in ethanol solution results in th
e binary metal iodide-iodine complexes [C6N4H13](2)(Hg2I6)(1/2)(HgI3) . 1/2
I-2, which are stable under ambient conditions. The structure consists of
C6N4H13+ cations, discrete trigonal HgI3- ions, and ...Hg2I62- ... I-2 ...H
g2I62- chains in the crystallographic b direction, which are formed by I-2
molecules connecting the bridging iodines of the Hg2I62- dimers. The intra-
and intermolecular I-I distances of iodine in the chain are 2.7402(15) and
3.438(1) Angstrom, respectively. The Raman spectrum of [C6N4H13](2)(Hg2I6)
(1/2)(HgI3) . 1/2 I-2 confirms the interaction between the iodine molecules
and Hg2I62- ions. The structure of [NH4](HgI3) . H2O, obtained during the
synthesis of [C6N4H13](2)(Hg2I6)(1/2)(HgI3) . 1/2 I-2, is also reported. Cr
ystal data for [C6N4H13](2)(Hg2I6)(1/2)(HgI3) . 1/2 I-2: a = 14.275(3) Angs
trom, b = 19.721(4) Angstrom, c = 10.416(2) Angstrom, orthorhombic space gr
oup Pbam; Z = 4. Crystal data for [NH4](HgI3) . H2O: a = 8.7246(4) Angstrom
, b = 9.7860(3) Angstrom, c = 11.1103(4) Angstrom, orthorhombic space group
Ama2; Z = 4.